stbatton



N0/ wy ,l un. H L%/ f/d w h w M n v IMM w v N, w i Q m o NS@ i w Y au umNX@ W UNITED STATES MILTON BOWKER AND JOSEPH L.

INSTRUMENT FOR sTEATToN, or rrToHEUEc, MAss.

DIVIDING CIRCLES.

Speciication forming part of Letters Patent-No. 99,824, dated Februaryl5, 15370.4

.To all whom it may concern:

Be it known that we, MILTON BowKEE and JOSEPH L. STEATTON, of Fitchburg,in the county of Worcester, in the State of Massachusetts, have inventeda new Tool for Dividing or Spacing Circles; and we do hereby declarethat thel following is a full and eXact description thereof, referencebeing had tothe accompanying drawings, and to the letters of referencemarked thereon.

In the construction of our invention two arms are joined in the forni ofa` rule or other joint, said arms being ot' any desirablelength, andupon one arm we attach the graduated quadrant curving to the left andpassing over the end of the other arm, upon which is placed anadjustable pointer,said pointer being heldin its position by thumb-nut;also, upon each arm is fastened what we term a check-spring. On theunder side of said springs a point is attached, extending through holesdrilled in said arms. Between the spring and joint upon the long arm isfastened a wire quadrant, curving to the left and passing through a studsaid stud being attached to the other or short arm, and upon the` wirequadrant is placed an adjustable check-collar, which is made fast with athumb-screw. In place of the wire quadrant, stud, check-collar, andthumbscrew, a slide :may be attached to the graduated quadrant. Throughthe stud in the joint upon which the arms swing is drilled a hole toreceive a center point, said point being adjustable and held in itsposition by a set-screw, said center being upon line of the front edgeof the long arm, and said arm being graduated in any desirable number ofgraduations, said graduations counting from centerof joint and numbered,so as to indicate the half or whole of a diameter. This tool can beconstructed of any suitable material.

In the drawings, Figure lis a plan View. Fig. 2 is a sectional View ofthe adjustable pointer e and thumb-nutf, showing the manner in which itis attached. Fig. 3 is an edge view of check-springs d and points Z.Fig. 4

is a sectional View of joint, showing the stud m, set-screw n, andpointed center o. v

In Fig. 1, a represents the `long graduated arm; b, the graduatedquadrant; c, the short arm; e, the adjustable pointer; l f, thumb-nut;d, the check-springs; K K, rivets or screws; g, wire quadrant; h, stud;t', check-collar; J, thumb-screw; m, joint-stud; o, the center point; n,set-screw.

To enable others skilled in the art to use our invention, we willproceed to describe its ,operation.

First, striking the circle you wish to divide, then place the tool uponthe board orbpaper on which the circle is drawn, placing the centerpoint o in the center of the circle; then slide arm c close to arm a,and adj ust pointer e to the zero-line; then slide arm c back until thepointer c indicates the number of divisions required in the circle; then.bring the set collar i close to studh and make fast with thumbscrew J;then again slide arm vc close to arm a; then press uponthe spring d onarm a over point d; then draw a line along the front edge of arm aacross the line of circle; then press on d, upon arm c, releasing springd upon arm a,- then slide forward arm a until checkcollar 'i comes incontact with stud h,- then again press upon spring d 'upon arm c,- thendraw another line as before, and you have one ofthe required divisions;and by repeating this operation any number of divisions can be obtainedfrom four to one hundred. Not deeming it necessary, and for want ofspace, We have not numbered all of the graduations on the quadrants.

Vhat we claim as our invention, and desire to secure by Letters Patent,is-

1. The springs d, points l, or their equivalent, for the purposespecified.

2. The combination of the adjustable center point, o, set-screw a, thewire quadrant g, set collar c', thumb-screw J, springs d, points Z,pointer e, nut f, arms a c, and quadrant b, with their graduations, allconstructed, combined, and arranged as hereinabove specied and shown.

MILTON BOW'KER. p JOSEPH L. STRATTON. Witnesses:

H. R. FRENCH, H. P. KAUFFER.

